A variety of dearomatized compounds have been prepared in moderate to excellent yields from planar scaffolds using trichloroisocyanuric acid (TCCA) as an atom-economical chlorinating agent. The method tolerates a broad range of functionalities and can take place in several green and/or sustainable solvents. Twenty-one examples of 1,1-dichlorinated products of dearomatized 2-naphthols and analogous heteroarenes (quinolinols, isoquinolinols, and quinazolinol) are reported along with five examples of monochlorinated dearomatized products.
View Article and Find Full Text PDFDrought can affect the capacity of soils to emit and consume biogenic volatile organic compounds (VOCs). Here we show the impact of prolonged drought followed by rewetting and recovery on soil VOC fluxes in an experimental rainforest. Under wet conditions the rainforest soil acts as a net VOC sink, in particular for isoprenoids, carbonyls and alcohols.
View Article and Find Full Text PDFIn the near future, climate change will cause enhanced frequency and/or severity of droughts in terrestrial ecosystems, including tropical forests. Drought responses by tropical trees may affect their carbon use, including production of volatile organic compounds (VOCs), with implications for carbon cycling and atmospheric chemistry that are challenging to predict. It remains unclear how metabolic adjustments by mature tropical trees in response to drought will affect their carbon fluxes associated with daytime CO2 production and VOC emission.
View Article and Find Full Text PDFSubst Use Misuse
May 2023
: Opioid and benzodiazepine-related deaths have been at all-time highs despite numerous changes to guidelines for prescribing these substances. Although prescribing guidelines appear to have resulted in fewer prescriptions from doctors, no recent study has looked at changes to where prescription drugs of misuse are obtained. : The purpose of this study was to examine trends in the source of prescription drug misuse between 2015 and 2019.
View Article and Find Full Text PDFMonoterpenes (CH) are emitted in large quantities by vegetation to the atmosphere (>100 TgC year), where they readily react with hydroxyl radicals and ozone to form new particles and, hence, clouds, affecting the Earth's radiative budget and, thereby, climate change. Although most monoterpenes exist in two chiral mirror-image forms termed enantiomers, these (+) and (-) forms are rarely distinguished in measurement or modelling studies. Therefore, the individual formation pathways of monoterpene enantiomers in plants and their ecological functions are poorly understood.
View Article and Find Full Text PDFPolycyclic hydrocarbons (PH) provide intriguing potential as lipophilic scaffolds within medicinal chemistry, but are currently limited by the availability of synthetic tools for predictable modification of the PH unit. Herein we report the development of new methods for installation of a sulfonamide unit to PH cores. In the first method, a xanthate ester serves as reagent for aminosulfonation using pre-formed imidoiodinane as N-source.
View Article and Find Full Text PDFSevere droughts endanger ecosystem functioning worldwide. We investigated how drought affects carbon and water fluxes as well as soil-plant-atmosphere interactions by tracing CO and deep water HO label pulses and volatile organic compounds (VOCs) in an enclosed experimental rainforest. Ecosystem dynamics were driven by different plant functional group responses to drought.
View Article and Find Full Text PDFRegional estimates of VOC fluxes focus largely on emissions from the canopy and omit potential contributions from the forest floor including soil, litter and understorey vegetation. Here, we measured monoterpene emissions every 2 months over 2 years from logged tropical forest and oil palm plantation floor in Malaysian Borneo using static flux chambers. The main emitted monoterpenes were α-pinene, β-pinene and d-limonene.
View Article and Find Full Text PDFIn fish, little is known about sex-specific differences in physiology and performance of the heart and whether these differences manifest during development. Here for the first time, the sex-specific heart rates during embryogenesis of , from the onset of the heart rates (HRs) to just prior to parturition, was investigated using light cardiogram. The genetic sex of the embryos was post-verified using a sex-specific genetic marker.
View Article and Find Full Text PDFThe field of social work seeks to enhance human well-being by addressing the needs of people living in poverty. Three billion people around the world use the internet daily, and 65% of them use social media. This article qualitatively identifies emergent themes about the lived experiences of poverty from people who reported either being poor or having have been poor, using selected social media posts (N = 1,495) on the website Reddit.
View Article and Find Full Text PDFObjectives: To examine the intersection of depression and alcohol use among older adults with multiple chronic health conditions (MCCs).
Design: Wave 1 data from the National Social Life, Health and Aging Project (2005-06).
Setting: Community-based sampling throughout the United States.
In most livebearing fish, the gravid spot is an excellent marker to identify brooding females, however its use to predict progress of embryonic development, brood size, timing of parturition and overall reproductive potential of populations remain unexplored. Therefore, to understand these relationships, this study quantified visual attributes (intensity and size) of the gravid spot in relation to key internal development in Gambusia holbrooki. Observations show that the colour of the gravid spot arises from progressive melanisation on the surface of the ovarian sac at its hind margin, rather than melanisation of the developing embryos or the skin of the brooding mother.
View Article and Find Full Text PDFUse of 'Judas' fish to betray the locations of conspecifics is a powerful tool in management of invasive pest fish but poses a risk of contributing to recruitment. Our aim therefore was to generate surgically sterilised male common carp (Cyprinus carpio) and test whether they readily assimilate into wild populations, retain sexual behaviour and successfully betray the locations of feral carp. Male common carp were surgically sterilised (n=44) adopting a two-point nip technique, using either a haemoclip, suture or electro cautery to tie each of the testicular ducts about 2.
View Article and Find Full Text PDFA novel titanium reaction cell has been constructed for the study of water-rock-CO2 reactions. The reaction cell has been used within a direct-sampling rocking autoclave and offers certain advantages over traditional "flexible gold/titanium cell" approaches. The main advantage is robustness, as flexible cells are prone to rupture on depressurisation during gas-rich experiments.
View Article and Find Full Text PDFCutan Ocul Toxicol
December 2012
Sunscreens are widely utilized due to the adverse effects of ultraviolet (UV) radiation on human health. The safety of their active ingredients as well as that of any modified versions generated during use is thus of concern. Chlorine is used as a chemical disinfectant in swimming pools.
View Article and Find Full Text PDFThe rate of the non-enzymatic hydrolysis of creatine ethyl ester (CEE) was studied at 37 degrees C over the pH range of 1.6-7.0 using (1)H NMR.
View Article and Find Full Text PDFBiochem Biophys Res Commun
April 1999
It has been found that melatonin reacts rapidly with hypochlorous acid in phosphate-buffered, ethanol-water solutions to produce 2-hydroxymelatonin. The rate law, d[2 - HOMel]/dt - kHOCl[Mel][HOCl] - kOCl-[Mel][OCl-], was obtained. At 37 degrees C and at a water concentration of 23.
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